1. Field of the Invention
The present invention relates to air data probes, and more particularly to moisture resistant inlets for air data probes.
2. Description of Related Art
A variety of air data probe devices are known in the art for aircraft flight control. Of such devices, many are directed to measuring pitot pressure, static pressure, local angle of attack pressures, and angle of sideslip pressures as parameters for calculating pressure altitude, altitude rate, airspeed, Mach number, angle of attack, and angle of sideslip. Air data probes can also provide data for secondary purposes including engine control, artificial feel, cabin pressure differential, and more.
The air data probe typically includes one or more static pressure ports located on the side of the probe head integral to the probe's surface which sense the atmospheric pressure outside of the aircraft, ideally without being influenced by pressure variances caused by movement of the aircraft. Static pressure is an important parameter that is utilized in aircraft for numerous purposes including the determination of altitude, altitude rate, airspeed and airspeed rate, which last-mentioned parameters are, in turn, used as inputs to various other devices such as flight management systems, autopilots, ground proximity warning systems and wind shear detectors.
FIG. 3 shows a portion of an air data probe 10 that is representative of the prior art. Air data probe 10 includes a probe head 12, an impact port inlet 14 opening along the longitudinal axis A of the probe head 12, a wall tap port inlet 16 with a circular inlet perimeter 18 and a plurality of conduits 20, 22 for fluid communication from port inlets 14 and 16 to internal components.
While the air data probe 10 represents the state of the art, during atmospheric moisture conditions, it is possible for the air data probe 10 to have pressure sensing measurement errors due to moisture being present on the surface of the air data probe 10 and also due to moisture being ingested into the impact port inlet 14 and wall tap port inlet 16. Such moisture includes solid and liquid moisture. During ground operation and in flight, atmospheric moisture can accumulate around and in pressure measuring ports. The wall tap port inlet 16 and other associated ports of an air data probe 10 can sometimes develop menisci, due to moisture accumulation, which affect the accuracy of the sensed pressures, and therefore affect the accuracy of the determined air speed, altitude, or other measured fluid dynamic characteristic.
Such conventional methods and systems generally have been considered satisfactory for their intended purpose. However, there remains an ever present need to advance the state of the art for reducing moisture meniscus formation in the wall tap port inlets of air data probes. There also remains a need in the art for methods and systems that are inexpensive and easy to make and use for reducing moisture accumulation for air data probes. The present invention provides a solution for these problems.